Method of manufacturing artificial limbs and similar devices



Nov. 27, 1928. t

I J. LOTH METHOD OF MANUFACTURING ARTIFICIAL LIMBS AND SIMILAR DEVICES Filed NOV. 11, 1927 //I V en for Julius [of W Q'czomgy Patented Nov. 27, 1 928.

un -T D STATES Partner OFFICE.

JULIUS LOTH, OF KOSLIN, GERMANY.

METHOD OF MANUFACTURING ARTIFICIAL'LIMBS AND SIMILAR DEVICES.

Application filed November 11, 1927, Serial No.-

The present invention relates to improvements :in or modifications of the invention claimed in copending. application Ser. No. 202,025. I r

The invention described in the saidcoered with a layer ofrso-called liquid wood.

As soon as this layer has set,v it is fixed by means of any suitable material such as wood,

Q metal, vulcanite fibre, leather and the like to the actualshell representing the true form of the leg.

This present invention constitutes a fur ther improvement of the said co-pending application and refers to an extremely simple process of afiixing the shell made of liquid wood to the limb.

According to this invention, the outer shell of the artificial limb is provided with apertures, a second layer of liquid wood is appliedto the shell made of liquid wood as soon as the first layer has set,'whereupon the shell made of liquid wood is pressed into the principal or outer shell. The liquid wood thereby penetrates into the apertures of the outer shell and by setting forms a solid unit which will not. slip. Any part or aperture possibly left out in the lower end of the innershell may be filled in with resin or the like.

The accompanying drawing gives a pos sible illustration of part of an artificial limb as constructed by the inventor.

As in the said co-pending application, so is a the plaster of Paris impression made in the usual way of the stump of the lower part of a leg. This impression is then covered with a layer 6 of liquid wood as described in the said co-pending application and is allowed to set thereby forming a shell around the stump impression. This shell I) may be closed at its lower end, as described in the co-pending application, or it may be left open in such manner as to allow the point of the stump to protrude. This latter method will be used in cases where the point of the stump should not receive any pressure. The outer shell i. e. the actual artificial limb is indicated at 0 and may consist of any desired material such as leather, metal, wood, vulcanite fibre and the like. I

According to the invention, the outer shell 232,622, and in Great Britain Aug st 1 1927.

is provided with apertures d at least at that part where the inner shell 6 is to be fitted but, these apertures are provided for all over the artificial limb c and. not less than the heights of the inner shell 6. tures d as shown in the drawing may be continued below the shell b but they would onlyconstitute a reduction in the weight ofthe whole limb and not serveto fulfill the purpose of the presentinvention.

A second layer 6 of liquid wood ispainted upon the shell b assoon as the one upon the stump has set whereuponthe shell 5 is pressed into the outer shell 0 while that layer is still liquid. This causes the material 6 which is still in a liquid state to extend into the apertures (Z of the outer shell 0 thereby forming when set, a solid mass 6 on the one hand, and a great number of plugs the size of the apertures (Z with a solid hold, on the other hand,

These ape r.

thereby connecting shells b and 0 by a firm and insoluble mass. In a case when the stump in its lower part is exceptionally pointed, a

proportionally large empty space may appear between the outer shell '0 and shell (Z thereby creating a gap. Thisgap, according to the invention, may befilled with any resinous matter, preferably an easily dissolved resin f, thus connecting shell Z) or material 6 on the one hand, and by extending into apertures d contributes to the solidification of shell 6 and shell 0.

Upon fixing shell Z) into shell 0 and upon con-sequent setting of the matter 6, the impression a of the stump, is eliminatedby means of breaking it to pieces. The material 6 is then covered on the inner side with any desired substance ora coat of paint,

By liquid wood is meant the material described in the said co-pending application consisting of finely dessicated wood, cork, shaving, or the like in connection with a binder. The binder may be for instance a glue, or it may be nitrated cellulose, or a s'im ilar material that has been dissolved in acetone or acetate and may have other ingrediliquid Wood, letting this layer solidity applying to it'a further layer of liquid Wood and inserting the thus obtained shell into an outer main shell provided With apertures While the second mentioned layer still is in a liquid state in such manner as to extend inserting the thus obtained shell into an-outer state in such a manner as to extend the liquid 2O main shell provided with apertures While the second mentioned layer still is in A liquid Wood into the apertures of the outer shell thus forming a solid unit of the'two shells When it has set and filling eventual gaps appearing between the inner shell of liquid Wood and the outer main shell With resin, whereby the resin or the like adheres to. the inner shellon the one hand and extends into the apertures of the outer shell on the other hand. I r

3. An artificial limb or the like consisting v ofa solidified layer of liquid Wood the inner shape of Which corresponds to the outer shape of thebody portion said layer being connected With a main shell of a suitable inaterialand an intermediate layer ofliquid Wood applied to said first named layer and'extending into apertures provided on said'main shell. I

4. An artificial limb or the like consisting of a solidified layer of liquid Woodthe inner shape of which corresponds to the outer shape of the body portion said layerbeing con nected with a mainshell of a suitable ma terial and an intermediate layer partly consisting-of liquid Wood and partly of resin applied to said first named layer andextending into apertures provided on said main shell.

In testimony whereof I have aflixed my signature. V

JULIUS LoTHQ I 

